Fastening strips with barbed closure elements

ABSTRACT

An interlocking closure fastening device comprises a pair of elongate closure elements. One of the closure elements has a barbed surface along a portion thereof. A second closure element includes a complemental surface that, when mated with the first surface, provides a perceptible tactile sensation.

FIELD OF THE INVENTION

The present invention relates to interlocking closure strips, and more particularly, an interlocking fastening strip that includes at least one barbed closure element particularly adapted for use with reclosable plastic storage bags.

BACKGROUND OF THF INVENTION

Known closure fastening devices used in conjunction with thermoplastic reclosable containers provide an effective seal of the contents in the container when the fastening device is placed in a closed position. Such fastening devices typically comprise a pair of complementary closure strip elements that extend longitudinally along the upper portions of opposed sidewalls of the containers. The closure elements are constructed such that they interlockingly engage with each other in a closed or occluded position, while at the same time permitting relatively easy disengagement of the closure elements when the container is opened from the outside.

One desirable feature of many such fastening devices is that they enable the user to determine the state of closure of the fastening device. For example, one known arrangement provides a visual indication of the closure state of the fastening device with the use of various colorations of the opposed closure elements. One such arrangement is disclosed in U.S. Pat. No. 4,829,641. When the opposed closure elements are interlocked, the user perceives a third distinct coloration of overlapping element portions indicative of proper closure of the container.

Other conventional techniques utilize a particular tactile “feel” provided to the user of the container to indicate closure of the container. For example, U.S. Pat. No. 5,070,584 discloses a zipper arrangement that provides the perception of a “bumpy” feel. The zipper arrangement includes a pair of opposing interlockable rib and groove profiles where one of the profiles has a plurality of indentations spaced longitudinally therealong. These indentations purportedly provide an audible clicking sound or bumpy feel that is perceptible to the user as the cutout or weakened portions flex during closure.

SUMMARY OF THE INVENTION

The present invention provides a fastening closure strip for use with a reclosable storage container that comprises a pair of interlocking closure elements. The fastening closure strip has a multiple position feature. In accordance with this invention, the user can move the closure strip from one position to another position. The engagement surfaces of the closures are referred to herein as barbed surfaces owing to the multiplicity of their engagement surfaces. One form of such engagement surfaces are often referred to as hooks. Accordingly, references herein to “hooks” are intended to refer to one type of a barb for use in this invention. At least one of the closure elements has a barbed surface to provide the user of the storage container a distinctive tactile “feel” when the container is closed.

Structurally, a closure fastening device according to the present invention comprises a pair of opposed, longitudinally extending closure strip elements adapted to interlockingly engage with each other a fully occluded mode. One of the closure element strips includes a plurality of barbs extending from an upright peripheral segment of the closure strip. The second closure element includes a complemental segment that intermittently engages the barbs as the closure elements are moved to the fully occluded mode upon the application of compression forces. This manner of engagement provides a ratcheting sensation to the user of the interlocking closure device.

In one embodiment, the first closure element strip comprises a base portion having a pair of spaced-apart, elongate first webs extending therefrom. The webs each include a male hook member extending outwardly from each of the respective webs. The second closure element similarly comprises a pair of webs extending from a second base portion. The second webs include a plurality of spaced-apart female barbs that extend inwardly to permit intermittent ratcheting engagement with the corresponding hook members when the fastening device is moved from a deoccluded mode to the occluded mode.

The invention may also be embodied in a closure fastening device comprising a first male closure element that includes a base portion having a pair of spaced-apart, elongate first webs extending therefrom. In this embodiment, the first webs each include a plurality of spaced-apart male barbs extending outwardly from each of the webs. The fastening device includes a female closure element having a pair of second webs extending from a second base portion. At least one of the second webs include a female hook member that extends inwardly to permit intermittent ratcheting engagement with the corresponding male barbs when the fastening device is moved from a deoccluded mode to the occluded mode.

In yet another embodiment, a closure fastening device comprises a male closure element with a pair of webs in the form of a serpentine profile configuration to provide a substantial wave like surface. This profile configuration forms a plurality of interleaved protrusions and corresponding depressions. The device further comprises a complementary female closure element including a pair of second webs, each of which has a female hook member adapted to intermittently engage the protrusions of the serpentine profile configuration.

Other advantages and embodiments of the invention will be apparent to those skilled in the art upon consideration of the following detailed description and appended claims, and upon reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a thermoplastic reclosable container that is suitable for incorporating the present invention.

FIG. 2 is a cross sectional view of a fastening device with at least one barbed closure element, taken along the lines 2-2 of FIG. 1, shown in a non-occluded position according to the present invention.

FIG. 3A is a cross-sectional view of one embodiment of the male closure element according to the invention showing the relative dimensions of the various elements of the male closure element.

FIG. 3B is a cross-sectional view of one embodiment of the female closure element according to the invention suitable for use with the male closure element of FIG. 3A and showing the relative dimensions of the various elements of the female closure element.

FIG. 4A and FIG. 4B are cross sectional views of the fastening device of FIG. 2 shown in various positions.

FIG. 5A is a cross sectional view of the fastening device of FIG. 2 in a fully occluded position.

FIG. 5B is a cross sectional view of another embodiment of the fastening device shown in FIG. 5A.

FIG. 6 is a cross sectional view of a fastening device shown in a non-occluded position according to a second embodiment of the present invention.

FIG. 7 and FIG. 8 are cross sectional views of the fastening device of FIG. 6 in various positions.

FIG. 9A is a cross sectional view of the fastening device of FIG. 6 in a fully occluded position.

FIG. 9B is a cross sectional view of another embodiment of the fastening device of FIG. 9A.

FIG. 10 is a cross sectional view of a fastening device shown in a non-occluded position according to a third embodiment of the present invention.

FIG. 11 and FIG. 12 are cross sectional views of the fastening device shown in FIG. 10 shown in various positions.

FIG. 13 is a cross sectional view of the fastening device of FIG. 10 in a fully occluded position.

FIG. 14 is a cross sectional view of a fastening device according to a fourth embodiment of the present invention shown in a partially occluded position.

FIG. 15 is a cross sectional view of the fastening device depicted in FIG. 14 shown in a fully occluded position.

FIG. 16 is a cross sectional view of another embodiment of the fastening device of FIG. 14.

FIG. 17 is a cross sectional view of another embodiment of the present invention.

FIG. 18 is a cross sectional view of another embodiment of the present invention.

FIG. 19 is a cross sectional view of another embodiment of the present invention.

FIG. 20A is a cross-sectional view of another embodiment shown in a non-occluded position.

FIG. 20B is a cross-sectional view of the fastening device in FIG. 20A in the occluded position.

FIG. 21 is a cross-sectional view of another embodiment.

FIG. 22 is a cross-sectional view of another embodiment.

FIG. 23 is a cross-sectional view of another embodiment.

FIG. 24 is a cross-sectional view of another embodiment.

FIG. 25 is a cross-sectional view of another embodiment.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Generally, the present invention relates to closure fastening strips that include complemental closure elements arranged to be interlocked over a preselected length of the strip. The fastening closure strip has a multiple position feature. In accordance with this invention, the user can move the closure strip from one position to another position. The engagement surfaces of the closures are referred to herein as barbed surfaces owing to the multiplicity of their engagement surfaces. One form of such engagement surfaces are often referred to as hooks. Accordingly, references herein to “hooks” are intended to refer to one type of a barb for use in this invention. At least one of the closure elements has a barbed surface used to interconnect a complementary closure element surface when the closure elements are placed in an occluded position. The barbed surface provides a feel of ratcheting engagement, as well as an audible sound, to a user of the plastic container upon the application of compressive forces to the closure bases to actively engage the barbs, effectively occluding the fastening strip.

FIG. 1 illustrates a thermoplastic container in the form of a plastic reclosable storage bag 4, that incorporates the teachings of the present invention. The storage bag 4 is formed of a relatively thin plastic film folded along the bottom to provide a pair of opposed sidewalls 6, 8 joined together along their side edges, and providing an opening or mouth 9 at the edge opposite the folded edge. FIG. 1 also shows a closure fastening device 10 including a pair of opposed closure elements 12 and 14 connected to the sidewalls. The closure elements 12, 14 preferably each comprise an elongate extruded plastic strip that together form a reclosable fastening device extending longitudinally between the side edges of the opposed sidewalls 6, 8, proximate to the opening of the storage bag 4.

FIG. 2 is a cross sectional view of the closure fastening device 10 illustrating one profile configuration according to the present invention. The device 10 includes a first closure element 12 and a second complementary closure element 14. In the embodiment shown, the closure elements are each plastic strips that include respective base portions which, in turn, are connected to the container sidewalls. The respective base portions are denoted in FIG. 1 by numerals 16, 18. Although the closure elements 12, 14 are illustrated as separately formed and thereafter connected to a plastic film which forms the sidewalls of the container, they may also be integrally formed with the container sidewalls in a conventional manner.

The structural details of the closure elements 12 and 14 are best seen in FIG. 2, as well as FIGS. 3A-4B. The first closure element 12 is a male element comprising a pair of spaced-apart webs 20, 22 disposed in parallel relation and extending generally orthogonally to the base portion 16. As used herein, the term “male” will refer to a closure element or portion that interfits into the mating closure element and has generally outwardly extending hooks or other interlocking portions. The outer element which generally has inwardly extending hooks or other portions will be referred to as a “female” closure element or portion. A pair of male hook members 24, 26 are attached to the respective legs such that they face outwardly from each other. In particular, the first male hook member 24 is disposed at the distal end of the first web 20 and protrudes outwardly therefrom. In this embodiment, one of the hook members 24 includes an inwardly extending guide surface 28 that extends at least partially inwardly from the first web 20. In operation, the guide surface 28 serves to guide the hook members for occlusion with the female barbs of a mating closure element, as described below. As noted above, the second web 22 has the male hook member 26 protruding outwardly from its distal end. This hook member includes a crowned or guide surface 30 that likewise facilitates engagement with the female barbs of the mating closure element. If desired, the guide surface 30 may extend inwardly from the web 22 similar to guide surface 28 and operate in a similar manner. In addition, the webs 20, 22 may each include two, three, four or more externally disposed barbs, as may be desired, such as the barbs 26 a-26 c, 24 a-24 c shown in FIG. 5B or the barbs 142 a-c, 146 a-c shown in FIG. 6.

The first closure element 12 also includes a pair of opposed winged guide members 32, 34 spaced laterally from the webs 20, 22 respectively. Preferably, the guide members 32, 34 are each constructed with end segments 32 e, 34 e that flare outwardly in order to funnel or guide the complementary webs of the second closure element 14 into alignment with the male hook members 24 and 26 as the closure elements are occluded, as described in greater detail below.

FIG. 2 illustrates the structural details of the second female closure element 14. This closure element similarly comprises first and second spaced-apart webs 36, 38 disposed in parallel relation and extending generally orthogonally from the base portion 18. The first web 36 includes a plurality of spaced-apart integrally formed female barbs 40 a, 40 b, 40 c, each of which extends inwardly from the first web 36. Each of the barbs 40 have generally contoured surfaces 42 a-c which guide the barbs 40 into mated engagement with the corresponding male hook member 24 of a mating closure element. The barbs further define a plurality of notches 44 a-c in the interstices between adjacent barbs. Likewise, the second web 38 includes a plurality of spaced-apart female barbs 46 a, 46 b, 46 c, which extend inwardly from the second web 38. These barbs 46 similarly have generally contoured surfaces 48 a-c which guide the barbs 46 into mated engagement with the corresponding male hook member 26 of a mating closure element. Likewise, the barbs 46 define a plurality of interdigital notches 50 a-c in the spaces between adjacent barbs. While this particular embodiment shows three barbs per web, each web may have two, three, four, or more barbs as may be desired.

In this embodiment, the closure element 14 includes a fin 52 extending from the base 18 between the webs 36, 38. The fin 52 may be included to maintain the structural integrity and facilitate the extrusion of the closure element 18. Similarly, closure element 12 may also include a fin extending from base 16. Furthermore, the closure elements 12, 14 may include one, two, three or more fins as may be desired. The fin may be used with any of the embodiments in this application as appropriate. In addition, the fin may also be designed to also function as a color enhancement member as described in U.S. Pat. No. 4,829,641, the subject matter of which is incorporated herein by reference.

The representative dimensions of a representative male closure element is shown in FIG. 3A where the dimensional values corresponding to the letters shown in the drawing are as follows: Parameter Range Preferred A 0.275-0.355 0.315 B 0.099-0.169 0.134 C 0.026-0.066 0.046 D 0.135-0.215 0.175 F 0.099-0.169 0.134 G 0.013-0.023 0.018

The female closure element used in conjunction with the male closure element of FIG. 3A is shown in FIG. 3B wherein the dimensional parameters are the following for a representative embodiment: Parameter Range Preferred H 0.235-0.315 0.275 I 0.108-0.178 0.143 J 0.013-0.033 0.023 K 0.012-0.022 0.017 L 0.037-0.067 0.052 M 0.023-0.053 0.038 N 0.013-0.023 0.018 O 0.013-0.023 0.018 P 0.013-0.023 0.018 Q 0.024-0.044 0.034

In operation, compression forces are applied to the opposed closure elements 12 and 14 in the directions denoted by the arrows 66, 68 shown in FIG. 4A and FIG. 4B, substantially normal to the plane of the respective container sidewalls and base portions 16, 18. Such forces are typically applied as the user engages the surfaces of the container and depresses or pinches his or her fingers along a desired length of the closure elements 12, 14. This action moves the opposed male hook members 24, 26 into contacting relation with the respective barb elements 40, 46 which flexes both pairs of webs to permit clearance of the hook members and barbs, as shown in FIGS. 4A and 4B. Thus, the respective female webs 36, 38 are flexed outwardly. At the same time, the respective webs 20, 22 of the male closure element 12 are flexed inwardly.

As the closure members are urged together, the male hook members 24, 26 intermittently engage corresponding ones of the barbs 40, 46 as the hook members are located within the notches disposed intermediate to the barbs. The closure elements thus temporarily achieve the orientation shown in FIG. 4B. In this way, the closure elements interlock in an interdigitating step-wise fashion until they are fully occluded, as shown in FIG. 5A. Accordingly, a ratcheting engagement of the male hook members with the barbs that is perceptible to the user occurs as the closure elements are urged together in an interdigitating fashion. In addition, this manner of ratcheting engagement generates an audible sound at each instance in which the hook member disengages from one of the barbs and is located within the notches formed therebetween due to the interdigitating nature of the opposed webs. The sound is caused by the ratcheting or snapping of the hook into the notch which results from the release of the flexure force of the hook. This sound is likewise readily perceptible by the user during a closure operation.

Preferably, each such intermittent engagement of the male hook elements with respective ones of the barbs provides sufficient interlocking engagement of the closure elements to maintain closure of the container. In most instances, however, the user will fully occlude the opposed closure members, in part due to the audible sound generated by the fastening device.

In order to deocclude the fastening device 10, the closure elements 12, 14 are urged apart from each other by pulling on the mouth portion of the plastic container (see FIG. 1). Such pulling action tends to urge the male webs 20, 22 inwardly and the female webs 36, 38 outwardly to permit passage of corresponding male hook members 24, 26 and barbs 40, 46. The same intermittent engagement is perceived by the user as a ratcheting of the closure elements 12, 14.

In FIGS. 1-5A, the webs 36, 38 have a barbed surface and the other webs 20, 22 have a complementary surface with a single barb. The ratcheting engagement is achieved when a single barb engages the barbed surface. However, as noted above, the webs 20, 22 could include multiple barbs as opposed to a single barb. Thus, a barbed surface would engage another barbed surface as shown in FIG. 5B. FIG. 5B is another embodiment of FIGS. 1-5A. The webs 20, 22 each include three externally disposed hooks 24 a-24 c, 26 a-26 c. Each of these hooks may be of the same size or some of the hooks may be of a different size, such as the smaller hooks 24 c, 26 c. The number and size of the hooks will depend upon the particular use for the fastening strip.

FIG. 6 shows the profile configuration of a fastening device 110 according to a second embodiment of the present invention. In this embodiment, a female closure element 112 includes inwardly oriented hook members which interlock with mating barbs of a male closure element 114. In particular, the female closure element 112 includes a pair of spaced-apart webs 120, 122 disposed in parallel relation and extending generally outwardly from a base portion 116. In this embodiment, the female webs 120, 122 each include a corresponding hook member 124, 126 disposed at their respective ends such that they protrude inwardly from each other. Each of the hook members 124, 126 are formed with a contoured surface 128, 130 to guide the hook members for occlusion with corresponding male barbs of a mating closure element. If desired each female web 120, 122 may include two, three or more hook members as shown by hook members 124 a-124 c, 126 a-126 c, in FIG. 9B.

The male closure element 114 comprises a base section 118 that similarly has a pair of spaced-apart webs 136, 138 extending outwardly from the base portion 118. A first one of the webs 136 includes a plurality of spaced-apart barbs 140 a-c, each of which extends outwardly from the first web 136. As with the female closure element described above, the barbs 140 are formed integrally with the first web 136 and have generally contoured surfaces 142 a-c which guide the barbs into mated engagement with the corresponding female hook member 124. The barbs 140 similarly define a plurality of interdigital notches 144 a-c in the spaces between the barbs. Likewise, the second web 138 includes a plurality of spaced-apart barbs 146 a-c which extend outwardly from the second web 138. The barb 146 a disposed at the distal end of the second web preferably includes an inwardly extending guide surface 148 a that extends at least partially inwardly from the second web 138. This guide surface 148 a assists in guiding the barb 146 a for occlusion with the mating female hook member. The remaining surfaces corresponding with the barbs 146 b and 146 c each include contoured surfaces 148 b-c to similarly facilitate engagement of the barbs 148 b-c with the mating female hook member. The barbs 146 additionally form a plurality of interdigital notches 150 a-c in the spaces between adjacent barbs. As with the embodiment described above, each web may similarly have two, three, four, or more barbs as may be desired.

The male closure element 114 also includes a pair of opposed winged guide members 132, 134 spaced laterally from the webs 136, 138. As with the guide members described above in connection with FIGS. 2-5, the guide members 132, 134 are each constructed with end segments 132 e, 134 e that flare outwardly away from respective webs 136, 136 in order to guide the webs 120, 122 of the female closure element into alignment with the male barbs when the closure elements are occluded.

In the illustrated embodiment, the female closure element 112 includes a fin 152 extending from the base 116 and the male closure element 114 includes a pair of spaced-apart fins 160, 162 extending from the base 118 intermediate the webs 136, 138. The fins 152, 160, 162 may be included to maintain the structural integrity and facilitate the extrusion of the closure elements 116, 118. The closure elements 112, 114 may include one, two, three or more fins as may be desired.

The operation of the closure fastening device shown in FIGS. 6-9B is similar to that described above. Compression forces similarly are applied to the opposed closure elements 112 and 114 in the direction denoted by the arrows 166, 168 in FIGS. 7 and 8, substantially normal to the plane of the respective base portions 116, 118. This action moves the opposed female hook members 124, 126 into contacting relation with the respective barbs 140, 146 which flexes both pairs of webs to permit clearance of the hook members and barbs. This permits intermittent ratcheting engagement of the hook members 124, 126 with corresponding ones of the barbs 140, 146 as the hook members are located within the interdigital notches 144, 150 formed between the barbs. Accordingly, a ratcheting engagement of the female hook members with the barbs that is perceptible to the user occurs as the closure elements are urged together. This ratcheting engagement likewise generates an audible sound at each instance in which the hook member disengages one of the barbs and is located within the notches. As noted above, the same ratcheting feel is perceived by the user when the closure elements 112, 114 are deoccluding.

Another embodiment of FIGS. 6-9A is shown in FIG. 9B. The webs 120, 122 each include three internally disposed hooks 124 a-124 c, 126 a-126 c. Each of these hooks may be of the same size or some of the hooks may be of a different size, such as the smaller hooks 124 c, 126 c. The number and size of the hooks will depend upon the particular use for the fastening strip.

FIG. 10, as well as FIGS. 11-13, illustrate cross sectional profile views of a third embodiment of the present invention. In this embodiment, a first female closure element 212 comprises a pair of spaced-apart webs 220, 222 extending outwardly from a base portion 216. The webs 220, 222 each include a hook elements 224, 226 disposed at the distal ends of the respective webs that are adapted to interlockingly engage segments of a second male closure element 214. Each web 220, 222 may include one, two, three or more hook members as may be desired. The second closure element 214 includes a pair of spaced-apart serpentine webs 236, 238 that extend generally outwardly from a base portion 218. In this embodiment, the first web 236 of the pair is of a wave like or serpentine configuration, and includes a plurality of spaced protrusions 240 a-c, each of which projects outwardly from the first web 236. The serpentine profile configuration also defines a plurality of spaced depressions 244 a-c in the spaces between the protrusions. Likewise, the second web 238 includes spaced protrusions 246 a-c, which extend outwardly from the second web 238. The profile configuration of the second web 238 similarly defines a plurality of spaced depressions 250 a-c intermediate to the protrusions. While the webs are shown with three protrusions and corresponding depressions, other numbers of protrusions and depressions may alternatively be utilized, such as, two protrusions and depressions, or four protrusions and depressions, or five or more protrusions and depressions. The protrusions are similar to barbs.

The male closure element 214 also includes a pair of guide members 232, 234. As noted above, the guide members 232, 234 are spaced laterally from the webs 236, 238, respectively. The first closure element 212 includes a fin 252 extending from the base 216 and the second closure element 214 includes two fins 260, 262 extending from the base 218. The fins 252, 260, 262 may be included to maintain the structural integrity and facilitate the extrusion of the closure elements. The closure elements 212, 214 may include one, two, three or more fins as may be desired.

In order to effectuate closure of the fastening device 210 shown in FIGS. 10-13, the opposed closure elements 212 and 214 are compressed in a direction substantially normal to the plane of the respective base portions 216, 218. The closure elements are thereby urged into contacting relation as the opposed female hook members 224, 226 abut against the ends of the respective serpentine webs 236, 238. This flexes both of the serpentine webs 236, 238 inwardly to permit clearance of the hook members and protrusions of the serpentine webs. At the same time, the respective female webs 220, 222 are urged outwardly to permit intermittent engagement of the hook members 224, 226 within corresponding depressions 244, 250 formed in the serpentine webs. This arrangement likewise provides an intermittent, ratcheting engagement of the female hook members 224, 226 as they traverse the serpentine webs that is readily perceptible to the user. The user likewise perceives such intermittent engagement when the closure elements are deoccluding. The webs may also have different configurations. For example, both webs could be serpentine and engage in an interdigitating fashion as in FIGS. 20A and 20B. Similarly, the webs could have a saw tooth configuration as in FIG. 21, or a series of rounded protrusions configuration as in FIG. 22. The webs could then provide multiple engagements after the first engagement. Several configurations can be utilized as long as the mating and contact points provide a leak resistant closure.

FIGS. 14 and 15 illustrate another embodiment of the present invention. In this embodiment, a fastening device 310 includes a plurality of spaced protrusions or bumped surfaces which are formed in the base portion of one of a pair of complementary closure elements. As shown, a first closure element 312 comprises a base portion 316 having a pair of inner male webs 320, 322 extending therefrom with male hook portions 324, 326 connected to the distal ends of the inner webs. The first hook portion 324 includes a crowned surface 330, while the second hook portion 326 includes an inwardly facing surface 328. A pair of outer webs 332, 334, spaced laterally from the inner webs 320, 322, extend from the base portion 316 a distance greater than the inner webs 320, 322. The outer webs 332, 334 can be oriented relative to said base in the range of 45-90 degrees with the range of 75-90 degrees preferred. In FIG. 14, the outer webs 332, 334 are oriented relative to the base 316 at an angle of approximately 82 degrees. The webs 332, 334 may have any configuration which will facilitate the movement of the webs 332, 334, such as curved ends 332 a, 334 a.

A second closure element 314 similarly comprises a base portion 318 with a pair of inner female webs 336, 338 with female hook portions 340, 342 located at the ends of the inner webs. Each of the female hook portions include an inwardly facing surface shown in FIGS. 14-15 as numerals 344, 346, respectively. As with the embodiments described above, these surfaces facilitate interlocking engagement of the male and female hook portions. The base portion 318 of the female closure element has a substantially greater width than that of the male closure element in order to provide a plurality of protrusions or bumped surfaces 340 a-c, 346 a-c extending beyond the outer ends of the male closure element base portion 316. A plurality of depressions 348 a-c, 350 a-c are thus formed intermediate the protrusions. While the illustrated embodiment employs three protrusions and corresponding depressions disposed at the outer ends of the base portion 316, one, two, three or more protrusions and depressions may also be used as desired.

In order to interlock the fastening device, a compression force is applied to the opposed closure elements 312, 314 such that the outer webs 332, 334 abut corresponding innermost protrusions 340 a, 346 a, as is shown in FIG. 14. As seen in FIG. 14, the male and female hook members are not yet in interlocking engagement. Further compression forces flex the outer webs 332, 334 such that the ends 332 a, 334 a are urged past the protrusions 340 a, 346 a, respectively, and are next located in the depressions 348 b, 350 b formed between the protrusions 340 a-b, 346 a-b. The outer webs are moved in step-wise fashion until they abut stop surfaces formed on the protrusions 340 c, 346 c, as shown in FIG. 15. In this position, the male and female closure elements are fully occluded. When the closure device is occluded as illustrated in FIG. 15, the outer webs 332, 334 are oriented relative to the base 316 at an angle of approximately 50 degrees. This arrangement likewise provides a ratcheting engagement of the outer webs with the depressions formed between laterally extending bumped surfaces that is perceptible to the user as the closure elements are urged together. In addition, an audible sound is generated.

Another embodiment of the spaced protrusions or bumps is shown in FIG. 16. In this embodiment the spaced protrusions have a saw tooth configuration. Specifically, the closure elements 412, 414 are similar to the closure elements 312, 314 noted above. However, the base portion 418 has a plurality saw tooth protrusions 440 a-440 c, 446 a-446 c. A plurality of depressions 448 a-448 d, 450 a-450 d are thus formed adjacent the protrusions. The outer webs 432, 434 are moved in a step-wise fashion until the webs abut stop surfaces 440 d, 446 d.

The closure device may include other types of closure elements. Referring to FIG. 17, the closure device includes a male closure element 512 and a female closure element 514. The male closure element includes a web 520 which extends from a base 516. The web 520 includes a head portion 524 and protrusions 527, 529. The female closure element 514 includes a channel 539 and two webs 541, 543 which extend from a base 518. The webs 541, 543 include barbs 545 a-545 c, 547 a-547 c and notches 549 a-549 c, 551 a-551 c adjacent the barbs. The barbs have generally contoured surfaces which guide the protrusions 527, 529 into mated engagement with the notches 549 a-549 c, 551 a-551 c. While this particular embodiment shows three barbs per wall, each wall may have one, two, four or more barbs as may be desired.

As the closure elements are urged together, the male protrusions 527, 529 intermittently engage corresponding ones of the barbs 545 a-545 c, 547 a-547 c as the protrusions 527, 529 are located within the notches 549 a-549 c, 551 a-551 c. The closure elements interlock in an interdigitating step-wise fashion until they are fully occluded. Accordingly, a ratcheting engagement of the protrusions with the barbs that is perceptible to the user occurs as the closure elements are urged together in an interdigitating fashion. In addition, this manner of ratcheting engagement generates an audible sound at each instance in which the protrusion disengages from one of the barbs and is located within the notches formed therebetween due to the interdigitating nature. The sound is caused by the ratcheting or snapping of the protrusion into the notch which results from the release of the flexure force of the barb. This sound is likewise readily perceptible by the user during a closure operation.

Another embodiment of the closure element with multiple barbs is shown in FIG. 18. The closure device includes a male closure element 612 and a female closure element 614. The male closure element 612 includes a web 620 which extends from a base 616. The web 620 includes a head portion 624, protrusions 627 a-627 c, 629 a-629 c and notches 649 a-649 c, 651 a-651 c. The female closure element 614 includes a channel 639 and two webs 641, 643 which extend from a base 618. The webs 641, 643 include barbs 645, 647. While this particular embodiment shows three protrusions on each side of the web, each side of the web may have one, two, four or more protrusions as may be desired.

As the closure elements are urged together, the male protrusions 627, 629 intermittently engage corresponding ones of the barbs 645, 647 as the barbs are located within the notches 649 a-649 c, 651 a-551 c. The closure elements interlock in an interdigitating step-wise fashion until they are fully occluded. Accordingly, a ratcheting engagement of the protrusions with the barbs that is perceptible to the user occurs as the closure elements are urged together in an interdigitating fashion. In addition, this manner of ratcheting engagement generates an audible sound at each instance in which the protrusion disengages from one of the barbs and is located within the notches formed therebetween due to the interdigitating nature. The sound is caused by the ratcheting or snapping of the barb into the notch which results from the release of the flexure force of the barb. This sound is likewise readily perceptible by the user during a closure operation.

The embodiment shown in FIG. 19 combines the female closure element of FIG. 17 with the male closure element in FIG. 18. The female closure element 714 is similar to female closure element 514 in FIG. 17. The male closure element 712 is similar to male closure element 612 in FIG. 18.

The female closure element 714 includes a channel 739 and two webs 741, 743 which extend from a base 718. The webs 741, 743 include barbs 745, 747 and notches 749, 751 adjacent the barbs. The barbs have generally contoured surfaces which guide the protrusions 727, 729 into mated engagement with the notches 749, 751. While this particular embodiment shows three barbs per wall, each wall may have one, two, four or more barbs as may be desired.

The male closure element 712 includes a web 720 which extends from a base 716. The web 720 includes a head portion 724, protrusions 727, 729 and notches 749, 751. While this particular embodiment shows three protrusions on each side of the web, each side of the web may have one, two, four or more protrusions as may be desired.

In order to effectuate closure of the fastening device 710 shown in FIG. 19, the opposed closure elements 712 and 714 are compressed in a direction substantially normal to the plane of the respective base portions 716, 718. The closure elements are thereby urged into contacting relation as the web 720 engages the respective webs 741, 743. The webs 741, 743 are urged outwardly to permit intermittent engagement of the barbs with the protrusions and intermittent engagement of the barbs and protrusions with the respective notches. This arrangement likewise provides an intermittent, ratcheting engagement that is readily perceptible to the user. The user likewise perceives such intermittent engagement when the closure elements are deoccluding.

Referring to FIGS. 20A and 20B, both webs could be serpentine and engage in an interdigitating fashion. The closure device 810 includes a first closure element 812 and a second closure element 814.

The first closure element 812 is similar to closure element 214 in FIGS. 10-13. The first closure element 812 includes a pair of spaced-apart serpentine webs 820, 822 that extend generally outwardly from a base portion 816. In this embodiment, the first web 820 of the pair is of a wave like or serpentine configuration, and includes a plurality of spaced protrusions 824 a-c, each of which projects outwardly from the first web 820. The serpentine profile configuration also defines a plurality of spaced depressions 825 a-c in the spaces between the protrusions. Likewise, the second web 822 includes spaced protrusions 826 a-c, which extend outwardly from the second web 822. The profile configuration of the second web 822 similarly defines a plurality of spaced depressions 827 a-c intermediate to the protrusions. While the webs are shown with three protrusions and corresponding depressions, other numbers of protrusions and depressions may alternatively be utilized, such as, two protrusions and depressions, or four protrusions and depressions, or five or more protrusions and depressions. The protrusions are similar to barbs.

The second closure element 814 is similar to the first closure element 812. The second closure element 814 includes a pair of spaced-apart serpentine webs 836, 838 that extend generally outwardly from a base portion 818. In this embodiment, the first web 836 of the pair is of a wave like or serpentine configuration, and includes a plurality of spaced protrusions 840 a-c, each of which projects outwardly from the first web 836. The serpentine profile configuration also defines a plurality of spaced depressions 844 a-c in the spaces between the protrusions. Likewise, the second web 838 includes spaced protrusions 846 a-c, which extend outwardly from the second web 838. The profile configuration of the second web 838 similarly defines a plurality of spaced depressions 850 a-c intermediate to the protrusions. While the webs are shown with three protrusions and corresponding depressions, other numbers of protrusions and depressions may alternatively be utilized, such as, two protrusions and depressions, or four protrusions and depressions, or five or more protrusions and depressions. The protrusions are similar to barbs.

The male closure element 814 also includes a pair of guide members 832, 834. As noted above, the guide members 832, 834 are spaced laterally from the webs 836, 838, respectively. The first closure element 812 includes a fin 852 extending from the base 816 and the second closure element 814 includes two fins 860, 862 extending from the base 818. The fins 852, 860, 862 may be included to maintain the structural integrity and facilitate the extrusion of the closure elements. The closure elements 812, 814 may include one, two, three or more fins as may be desired.

In order to effectuate closure of the fastening device 810 shown in FIG. 20A, the opposed closure elements 812 and 814 are compressed in a direction substantially normal to the plane of the respective base portions 816, 818. The closure elements are thereby urged into contacting relation as the opposed serpentine webs 820, 822 abut against the respective serpentine webs 836, 838. The serpentine webs 836, 838 flex inwardly to permit intermittent engagement of the protrusions with the other protrusions and intermittent engagement of the protrusions with the depressions. At the same time, the respective webs 820, 822 are urged outwardly to permit intermittent engagement of the protrusions with the other protrusions and intermittent engagement of the protrusions with the depressions. This arrangement likewise provides an intermittent, ratcheting engagement that is readily perceptible to the user. The user likewise perceives such intermittent engagement when the closure elements are deoccluding.

Referring to FIG. 21, both webs could have a saw tooth configuration and engage in an interdigitating fashion. The closure device 910 includes a first closure element 912 and a second closure element 914.

The first closure element 912 includes a pair of spaced-apart webs 920, 922 that extend generally outwardly from a base portion 916. In this embodiment, the first web 920 of the pair includes a plurality of spaced triangular protrusions 924, each of which projects outwardly from the first web 920. The profile configuration also defines a plurality of spaced depressions 925 in the spaces between the protrusions. Likewise, the second web 922 includes spaced triangular protrusions 926, which extend outwardly from the second web 922. The profile configuration of the second web 922 similarly defines a plurality of spaced depressions 927 intermediate to the protrusions. While the webs are shown with four protrusions and corresponding depressions, other numbers of protrusions and depressions may alternatively be utilized, such as, two protrusions and depressions, or three protrusions and depressions, or five or more protrusions and depressions. The protrusions are similar to barbs.

The second closure element 914 is similar to the first closure element 912. The second closure element 914 includes a pair of spaced-apart webs 936, 938 that extend generally outwardly from a base portion 918. In this embodiment, the first web 936 of the pair includes a plurality of spaced triangular protrusions 940, each of which projects outwardly from the first web 936. The profile configuration also defines a plurality of spaced depressions 944 in the spaces between the protrusions. Likewise, the second web 938 includes spaced triangular protrusions 946, which extend outwardly from the second web 938. The profile configuration of the second web 938 similarly defines a plurality of spaced depressions 950 intermediate to the protrusions. While the webs are shown with four protrusions and corresponding depressions, other numbers of protrusions and depressions may alternatively be utilized, such as, two protrusions and depressions, or three protrusions and depressions, or five or more protrusions and depressions. The protrusions are similar to barbs.

The male closure element 914 also includes a pair of guide members 932, 934. As noted above, the guide members 932, 934 are spaced laterally from the webs 936, 938, respectively. The first closure element 912 includes a fin 952 extending from the base 916 and the second closure element 914 includes two fins 960, 962 extending from the base 918. The fins 952, 960, 962 may be included to maintain the structural integrity and facilitate the extrusion of the closure elements. The closure elements 912, 914 may include one, two, three or more fins as may be desired.

In order to effectuate closure of the fastening device 910 shown in FIG. 21, the opposed closure elements 912, 914 are compressed in a direction substantially normal to the plane of the respective base portions 916, 918. The closure elements are thereby urged into contacting relation as the opposed webs 920, 922 abut against the respective webs 936, 938. The webs 936, 938 flex inwardly to permit intermittent engagement of the protrusions with the other protrusions and intermittent engagement of the protrusions with the depressions. At the same time, the respective webs 920, 922 are urged outwardly to permit intermittent engagement of the protrusions with the other protrusions and intermittent engagement of the protrusions with the depressions. This arrangement likewise provides an intermittent, ratcheting engagement that is readily perceptible to the user. The user likewise perceives such intermittent engagement when the closure elements are deoccluding.

The triangular protrusions 924, 926, 940, 946 are designed so that the force required to occlude the closure device is less than the force required to deocclude the closure device. Specifically, the faces of the triangular protrusions which contact during occlusion are at an angle which will facilitate occlusion. The faces of the triangular protrusions which contact during deocclusion are horizontal which will make deocclusion more difficult than occlusion. The angles of the faces can be changed to achieve the desired results.

Referring to FIG. 22, both webs could have a rounded protrusions configuration and engage in an interdigitating fashion. The closure device 1010 includes a first closure element 1012 and a second closure element 1014.

The first closure element 1012 includes a pair of spaced-apart webs 1020, 1022 that extend generally outwardly from a base portion 1016. In this embodiment, the first web 1020 of the pair includes a plurality of spaced rounded protrusions 1024, each of which projects outwardly from the first web 1020. The profile configuration also defines a plurality of spaced depressions 1025 in the spaces between the protrusions. Likewise, the second web 1022 includes spaced rounded protrusions 1026, which extend outwardly from the second web 1022. The profile configuration of the second web 1022 similarly defines a plurality of spaced depressions 1027 intermediate to the protrusions. While the webs are shown with three protrusions and corresponding depressions, other numbers of protrusions and depressions may alternatively be utilized, such as, two protrusions and depressions, or four protrusions and depressions, or five or more protrusions and depressions. The protrusions are similar to barbs.

The second closure element 1014 is similar to the first closure element 1012. The second closure element 1014 includes a pair of spaced-apart webs 1036, 1038 that extend generally outwardly from a base portion 1018. In this embodiment, the first web 1036 of the pair includes a plurality of spaced rounded protrusions 1040, each of which projects outwardly from the first web 1036. The profile configuration also defines a plurality of spaced depressions 1044 in the spaces between the protrusions. Likewise, the second web 1038 includes spaced rounded protrusions 1046, which extend outwardly from the second web 1038. The profile configuration of the second web 1038 similarly defines a plurality of spaced depressions 1050 intermediate to the protrusions. While the webs are shown with three protrusions and corresponding depressions, other numbers of protrusions and depressions may alternatively be utilized, such as, two protrusions and depressions, or four protrusions and depressions, or five or more protrusions and depressions. The protrusions are similar to barbs.

The second closure element 1014 also includes a pair of guide members 1032, 1034. As noted above, the guide members 1032, 1034 are spaced laterally from the webs 1036, 1038, respectively. The first closure element 1012 includes a fin 1052 extending from the base 1016 and the second closure element 1014 includes two fins 1060, 1062 extending from the base 1018. The fins 1052, 1060, 1062 may be included to maintain the structural integrity and facilitate the extrusion of the closure elements. The closure elements 1012, 1014 may include one, two, three or more fins as may be desired.

In order to effectuate closure of the fastening device 1010 shown in FIG. 22, the opposed closure elements 1012 and 1014 are compressed in a direction substantially normal to the plane of the respective base portions 1016, 1018. The closure elements are thereby urged into contacting relation as the opposed webs 1020, 1022 abut against the respective webs 1036, 1038. The webs 1036, 1038 flex inwardly to permit intermittent engagement of the protrusions with the other protrusions and intermittent engagement of the protrusions with the depressions. At the same time, the respective webs 1020, 1022 are urged outwardly to permit intermittent engagement of the protrusions with the other protrusions and intermittent engagement of the protrusions with the depressions. This arrangement likewise provides an intermittent, ratcheting engagement that is readily perceptible to the user. The user likewise perceives such intermittent engagement when the closure elements are deoccluding.

FIG. 23 illustrates another embodiment of the present invention. In this embodiment, a fastening device 1110 includes outer webs with a barbed surface which are disposed at an angle to the base portion. The fastening device 1110 includes a first closure element 1112 and a second closure element 1114. The first closure element 1112 includes inner webs 1120, 1122 and a base 1116 which are similar to webs 120, 122 and base 116 in FIG. 6. The first closure element 1112 also includes outer webs 1132, 1134 which are disposed at an angle to the base portion 1116. The outer webs 1132, 1134 can be oriented relative to said base in the range of 30-60 degrees with the angle of 45 degrees preferred. In FIG. 23, the outer webs 1132, 1134 are oriented relative to the base at an angle of approximately 45 degrees. The outer webs 1132, 1134 include barbed surfaces 1140, 1146. While this embodiment employs surfaces 1140, 1146, other embodiments may use other surfaces, such as surfaces 340, 346 in FIGS. 14-15 or surfaces 440, 446 in FIG. 16.

The second closure element 1114 includes inner webs 1121, 1123 and a base 1117 which are similar to webs 20, 22 and base 16 in FIG. 2. The second closure element 1114 also includes outer webs 1133, 1135 which are disposed at an angle to the base portion 1117. The outer webs 1133, 1135 can be oriented relative to said base in the range of 30-60 degrees with the angle of 45 degrees preferred. In FIG. 23, the outer webs 1133, 1135 are oriented relative to the base at an angle of approximately 45 degrees. The outer webs 1133, 1135 include barbed surfaces 1141, 1145. The barbed surface may have any configuration which will appropriately engage the corresponding web.

In this embodiment, the barbed surface includes triangular protrusions. The triangular protrusions are designed to control the magnitude of the tactile sensation both during opening and closing of the closure device. Specifically, the faces of the triangular protrusions which contact during occlusion are at an angle which will create a strong tactile sensation during occlusion. The faces of the triangular protrusions which contact during deocclusion are substantially vertical which will create a reduced or mild tactile sensation during occlusion. The angle of the faces can be changed to achieve the desired results.

The fastening device 1110 is shown in the occluded position in FIG. 23. Compression forces are applied to the closure elements 1112, 1114 and the webs are urged into contact with each other. The inner webs engage as noted above with respect to FIGS. 14-16. The outer webs flex as the barbed surface of one web 1134, 1135 engage the barbed surface of the other web 1132, 1133. This action permits intermittent ratcheting engagement in an interdigitating fashion. Accordingly, a ratcheting engagement is perceptible to the user as the closure elements are urged together in an interdigitating fashion. In addition, this manner of ratcheting engagement may generate an audible sound perceptible to the user during the closure operation. The ratcheting feel may be perceived by the user when the closure elements are deoccluding.

FIG. 24 illustrates another embodiment of the present invention. In this embodiment, the fastening device includes inner webs with barbed surfaces and outer webs with barbed surfaces. The fastening device 1210 includes a first closure element 1212 and a second closure element 1214. The first closure element 1212 includes inner webs 1220, 1222 and a base 1216 which are similar to webs 120, 122 and base 116 in FIG. 9B. While this embodiment employs webs 1220, 1222, other embodiments may use other webs, such as, the webs in FIGS. 2-9A, 10-13, and 17-22. The first closure element 1212 also includes outer webs 1232, 1234 which are similar to webs 1132, 1134 in FIG. 23.

The second closure element 1214 includes inner webs 1236, 1238 and a base 1218 which are similar to webs 136, 138 and base 118 in FIG. 9B. While this embodiment employs webs 1220, 1222, other embodiments may use other webs, such as, the webs in FIGS. 2-9A, 10-13, and 17-22. The second closure element 1214 also includes outer webs 1233, 1235 which are similar to webs 1133, 1135 in FIG. 23.

The fastening device 1210 is shown in the occluded position in FIG. 24. Compression forces are applied to the closure elements 1212, 1214 and the webs are urged into contact with each other. The inner webs engage as noted above with respect to FIGS. 6-9A and especially FIG. 9B. The outer webs engage as noted above for FIG. 23. The ratcheting engagement of the inner webs and outer webs is perceptible to the user as the closure elements are urged together in an interdigitating fashion. In addition, this manner of ratcheting engagement may generate an audible sound perceptible to the user during a closure operation. The ratcheting feel may be perceived by the user when the closure elements are deoccluding.

FIG. 25 illustrates another embodiment of the invention. In this embodiment, the fastening device includes inner webs with barbed surfaces and a barbed surface on the base portion of one of the closure elements. The fastening device 1310 includes a first closure element 1312 and a second closure element 1314. The first closure element 1312 includes inner webs 1320, 1322 and a base 1316 which are similar to webs 1220, 1222 and base 1216 in FIG. 24. While this embodiment employs webs 1320, 1322, other embodiments may use other webs, such as, the webs in FIGS. 2-13 and 17-22. The first closure element 1212 includes a barbed surface 1340, 1346 on the base which are similar to surfaces 440, 446 in FIG. 16. While this embodiment employs barbed surfaces 1340, 1346, other embodiments may use other surfaces, such as, surfaces 340, 346 in FIGS. 14 and 15.

The second closure element 1314 includes inner webs 1336, 1338 and a base 1318 which are similar to webs 1236, 1238 and base 1218 in FIG. 24. While this embodiment employs webs 1336, 1338, other embodiments may use other webs, such as, the webs in FIGS. 2-13 and 17-22. The second closure element 1314 also includes outer webs 1332, 1334 which are similar to webs 432, 434 in FIG. 16.

The fastening device 1010 is shown in the occluded position in FIG. 25. Compression forces are applied to the closure elements 1312, 1314 and the webs are urged into contact with each other. The inner webs engaged as noted above with respect to FIG. 24. The outer webs engage as noted above for FIG. 16. The ratcheting engagement of the inner webs and the outer webs is perceptible to the user as the closure elements are urged together in an interdigitating fashion. In addition, this manner of ratcheting engagement may generate an audible sound perceptible to the user during a closure operation. The ratcheting feel may be perceived by the user when the closure elements are deoccluding.

The closure fastening devices of this invention are preferably formed from thermoplastic materials such as high, medium or low density polyethylene or from other resins. Such fastening devices can readily be manufactured by known methods such as by extrusion, by the use of molds or other known methods of producing such devices. They can be manufactured as a strip for later attachment to a plastic film or they can be formed integral with the film. In the instance where formed by extrusion, the closure fastening devices may be extruded with or without flange portions on one or both of the closure elements depending on the particular manufacturing operations utilized.

There are various advantages to the fastening device according to the present invention. For example, the barbed arrangement provides an enhanced feel to the user. Furthermore, the present invention provides an enhanced feel with an arrangement that provides various points of occlusion. In addition, the invention, when utilized in an arrangement comprising multiple barbs, may provide step-wise color enhancement to provide various degrees of visual indication. In particular, the user may perceive different shades of color change depending on the level of occlusion of the barbs with corresponding hooks when looking at the fastening device from the side.

Accordingly, a closure fastening device that includes a first closure element with at least one barbed surface and a second closure element with a complementary mating surface that provides intermittent ratcheting engagement with the barbed surface that meets the aforestated objectives has been described. In this way, the user perceives a tactile feel as the closure elements are engaged. It will be apparent to those skilled in the art that a number of modifications can be made to the invention disclosed, particularly by those having the benefit of the foregoing teachings, without departing from the spirit of these principles. Accordingly, it is intended that the invention be limited only by the scope of the appended claims. 

1. An interlocking closure fastening device comprising a pair of opposed, longitudinally extending closure elements adapted to interlockingly engage with each other, the first closure element having a first barbed surface extending along a segment thereof, and a second closure element including a first complementary surface disposed along a segment thereof, said first complementary surface being in engagement with said first barbed surface in an occluded position, the surfaces providing ratcheting engagement upon the application of compression forces to the first and second closure elements.
 2. The invention as in claim 1 wherein said first closure element includes a base and said first barbed surface is oriented at an angle in the range of 0°-90° relative to said base.
 3. The invention as in claim 2 wherein said first barbed surface is oriented at an angle of substantially 90° to said base.
 4. The invention as in claim 3 wherein said first closure element includes a web and said first barbed surface is located on said web.
 5. The invention as in claim 4 wherein said first barbed surface includes a plurality of hooks.
 6. The invention as in claim 4 wherein said first barbed surface includes a plurality of saw teeth.
 7. The invention as in claim 4 wherein said first barbed surface includes a plurality of protrusions.
 8. The invention as in claim 4 wherein said first barbed surface has a serpentine configuration.
 9. The invention as in claim 4 wherein said first complementary surface has a barb.
 10. The invention as in claim 4 wherein said first complementary surface has a barbed surface.
 11. The invention as in claim 10 wherein said barbed surfaces include a plurality of hooks.
 12. The invention as in claim 10 wherein said barbed surfaces include a plurality of saw teeth.
 13. The invention as in claim 10 wherein said barbed surfaces include a plurality of protrusions.
 14. The invention as in claim 10 wherein said barbed surfaces have a serpentine configuration.
 15. The invention as in claim 3 wherein said first closure element includes two webs and said first barbed surface is located on one of said webs and a second barbed surface is located on said other web.
 16. The invention as in claim 15 wherein said barbed surfaces include a plurality of hooks.
 17. The invention as in claim 15 wherein said barbed surfaces include a plurality of saw teeth.
 18. The invention as in claim 15 wherein said barbed surfaces include a plurality of protrusions.
 19. The invention as in claim 15 wherein said barbed surfaces have a serpentine configuration.
 20. The invention as in claim 15 wherein said first complementary surface has a barb.
 21. The invention as in claim 15 wherein said first complementary surface has a barbed surface and said second closure element includes a second complementary surface, said second complementary surface has a barbed surface.
 22. The invention as in claim 21 wherein said barbed surfaces include a plurality of hooks.
 23. The invention as in claim 21 wherein said barbed surfaces include a plurality of saw teeth.
 24. The invention as in claim 21 wherein said barbed surfaces include a plurality of protrusions.
 25. The invention as in claim 21 wherein said barbed surfaces have a serpentine configuration.
 26. The invention as in claim 15 wherein said barbed surfaces face inward.
 27. The invention as in claim 15 wherein said barbed surfaces face outward.
 28. The invention as in claim 15 wherein said first barbed surface has a different configuration than said second barbed surface.
 29. The invention as in claim 3 wherein said first closure element includes a first web, a second web, a third web and a fourth web, said first barbed surface located on said first web, said second web includes a second barbed surface, said second barbed surface oriented at an angle of substantially 90° to said base, said third web includes a third barbed surface, and said fourth web includes a fourth barbed surface.
 30. The invention as in claim 29 wherein said third web is parallel to said base.
 31. The invention as in claim 29 wherein said third web is oriented at an angle greater than 0° relative to said base.
 32. The invention as in claim 2 wherein said first closure element includes a base and said first barbed surface is substantially parallel to said base.
 33. The invention as in claim 32 wherein said first barbed surface is integral with said base.
 34. The invention as in claim 32 wherein said first barbed surface includes a plurality of saw teeth.
 35. The invention as in claim 32 wherein said first barbed surface includes a plurality of protrusions.
 36. The invention as in claim 32 wherein said second closure element includes a web and said first complementary surface is disposed along said web.
 37. The invention as in claim 32 wherein said first closure element includes a second barbed surface.
 38. The invention as in claim 37 wherein said second barbed surface is substantially parallel to said base.
 39. The invention as in claim 37 wherein said second closure element includes a web and a second complementary surface along said web.
 40. The invention as in claim 37 wherein said second barbed surface is oriented at an angle of substantially 90° to said base.
 41. The invention as in claim 36 wherein said first complementary surface includes a barb.
 42. A container comprising two opposed sidewalls and an interlocking fastening device, the fastening device including a first closure element secured to one of the sidewalls, the first closure element having a first barbed surface along a segment thereof, and a second closure element secured to the second sidewall, the second closure element including a first complementary surface along a segment thereof, said first complementary surface being in mated interlocking engagement with said first barbed surface in an occluded position, the surfaces providing ratcheting engagement when urged from an deoccluded position to the occluded position.
 43. The invention as in claim 42 wherein said first closure element includes a base and said first barbed surface is oriented at an angle in the range of 0°-90° relative to said base.
 44. The invention as in claim 43 wherein said first barbed surface is oriented at an angle of substantially 90° to said base.
 45. The invention as in claim 44 wherein said first closure element includes a web and said first barbed surface is located on said web.
 46. The invention as in claim 45 wherein said first barbed surface includes a plurality of hooks.
 47. The invention as in claim 45 wherein said first barbed surface includes a plurality of saw teeth.
 48. The invention as in claim 45 wherein said first barbed surface includes a plurality of protrusions.
 49. The invention as in claim 45 wherein said first barbed surface has a serpentine configuration.
 50. The invention as in claim 45 wherein said first complementary surface has a barb.
 51. The invention as in claim 45 wherein said first complementary surface has a barbed surface.
 52. The invention as in claim 51 wherein said barbed surfaces include a plurality of hooks.
 53. The invention as in claim 51 wherein said barbed surfaces include a plurality of saw teeth.
 54. The invention as in claim 51 wherein said barbed surfaces include a plurality of protrusions.
 55. The invention as in claim 51 wherein said barbed surfaces have a serpentine configuration.
 56. The invention as in claim 44 wherein said first closure element includes two webs and said first barbed surface is located on one of said webs and a second barbed surface is located on said other web.
 57. The invention as in claim 56 wherein said barbed surfaces include a plurality of hooks.
 58. The invention as in claim 56 wherein said barbed surfaces include a plurality of saw teeth.
 59. The invention as in claim 56 wherein said barbed surfaces include a plurality of protrusions.
 60. The invention as in claim 56 wherein said barbed surfaces have a serpentine configuration.
 61. The invention as in Claim 56 wherein said first complementary surface has a barb.
 62. The invention as in claim 56 wherein said first complementary surface has a barbed surface and said second closure element includes a second complementary surface, said second complementary surface has a barbed surface.
 63. The invention as in claim 62 wherein said barbed surfaces include a plurality of hooks.
 64. The invention as in claim 62 wherein said barbed surfaces include a plurality of saw teeth.
 65. The invention as in claim 62 wherein said barbed surfaces include a plurality of protrusions.
 66. The invention as in claim 62 wherein said barbed surfaces have a serpentine configuration.
 67. The invention as in claim 56 wherein said barbed surfaces face inward.
 68. The invention as in claim 56 wherein said barbed surfaces face outward.
 69. The invention as in claim 56 wherein said first barbed surface has a different configuration than said second barbed surface.
 70. The invention as in claim 44 wherein said first closure element includes a first web, a second web, a third web and a fourth web, said first barbed surface located on said first web, said second web includes a second barbed surface, said second barbed surface oriented at an angle of substantially 90° to said base, said third web includes a third barbed surface, and said fourth web includes a fourth barbed surface.
 71. The invention as in claim 70 wherein said third web is parallel to said base.
 72. The invention as in claim 70 wherein said third web is oriented at an angle greater than 0° relative to said base.
 73. The invention as in claim 43 wherein said first closure element includes a base and said first barbed surface is substantially parallel to said base.
 74. The invention as in claim 73 wherein said first barbed surface is integral with said base.
 75. The invention as in claim 73 wherein said first barbed surface includes a plurality of saw teeth.
 76. The invention as in claim 73 wherein said first barbed surface includes a plurality of protrusions.
 77. The invention as in claim 73 wherein said second closure element includes a web and said first complementary surface is disposed along said web.
 78. The invention as in claim 73 wherein said first closure element includes a second barbed surface.
 79. The invention as in claim 78 wherein said second barbed surface is substantially parallel to said base.
 80. The invention as in claim 78 wherein said second closure element includes a web and a second complementary surface along said web.
 81. The invention as in claim 78 wherein said second barbed surface is oriented at an angle of substantially 90° to said base.
 82. The invention as in claim 77 wherein said first complementary surface includes a barb. 